THE SURFACE INFILTRATION-MODEL

Detailed rainfall and runoff recorded information from different plot sizes, constructed in natural hillslopes, was analyzed to obtain the ' 'apparent infiltration'' values. These values demonstrate an increase of the apparent infiltration rates at high rainfall intensity segments . The purpose of this study is to quantitatively understand runoff gen eration, on natural slopes, by combining detailed rainfall intensity i nformation with surface characteristics, which ave the main control of rainfall-runoff relations. The concept of looking at any unit area as a dynamic mosaic of contributors and sinks is the main idea of the pr oposed model. The model helped to explore sets of stable infiltration parameters, which depend mainly on surface characteristics and min int ensities. They varied little throughout the 2 years of the study. Meas ured and calculated runoff compared very well.